The Faucet

THE FAUCET

Tabish Nawaz / June, 2018 / Leave a comment / Poetry

The faucet in our kitchen is getting old
I had touched it
When we came to see the apartment
The first one of our married life
The faucet had moved up and down and right and left
To converse with
The echo our words birthed
To give each other company
It coughed and spit
A few words in exchange
The heads turned to see and listen
Pleased by attention
The faucet began flowing
Weaving words and verses
Warm and cool together
The apartment awakened
Life flowing through its veins
Carried us into its heart
It is two years since we moved in
The water no longer is sweet
The words have become brackish
We both thought
Maybe it is time
Things, as us, age
Faucets in particular
Wear and tear of motion
Of moisture held within
From outside we fixed
Inexperienced as we were of inner workings
A faucet filter atop its lips
Now a switch governs
The sweetness of its water
A light blinks green
To ensure us that everything is fine
It seems fine
But when we withdraw to our beds
The silence sneaks in
The spaces between us
The water held within
The faucet’s lips, like words,
Fall, one by one
With a sound lulling us to sleep
and sometimes to think, if
The water within its lips
Is sweet or brackish
We wish it be as sweet
when nothing guarded
The faucet’s lips.

The Faucet was first published in The Bangalore Review

http://bangalorereview.com/2018/06/the-faucet/

Silver nanoparticles in clothing wash out – and may threaten human health and the environment

Humans have known since ancient times that silver kills or stops the growth of many microorganisms. Hippocrates, the father of medicine, is said to have used silver preparations for treating ulcers and healing wounds. Until the introduction of antibiotics in the 1940s, colloidal silver (tiny particles suspended in a liquid) was a mainstay for treating burns, infected wounds and ulcers. Silver is still used today in wound dressings, in creams and as a coating on medical devices.

Since the 1990s, manufacturers have added silver nanoparticles to numerous consumer products to enhance their antibacterial and anti-odor properties. Examples include clothes, towels, undergarments, socks, toothpaste and soft toys. Nanoparticles are ultra-small particles, ranging from 1 to 100 nanometers in diameter – too small to see even with a microscope. According to a widely cited database, about one-fourth of nanomaterial-based consumer products currently marketed in the United States contain nanosilver.

Korean toothpaste containing nanosilver. Alex Parlini, Project on Emerging Nanotechnologies, CC BY-ND

Multiple studies have reported that nanosilver leaches out of textiles when they are laundered. Research also reveals that nanosilver may be toxic to humansand aquatic and marine organisms. Although it is widely used, little is understood about its fate or long-term toxic effects in the environment.

We are developing ways to convert this potential ecological crisis into an opportunity by recovering pure silver nanoparticles, which have many industrial applications, from laundry wastewater. In a recently published study, we describe a technique for silver recovery and discuss the key technical challenges. Our approach tackles this problem at the source – in this case, individual washing machines. We believe that this strategy has great promise for getting newly identified contaminants out of wastewater.

A textile silver lode

Use of nanosilver in consumer products has steadily risen in the past decade. The market share of silver-based textiles rose from 9 percent in 2004 to 25 percent in 2011.

Several investigators have measured the silver content of textiles and found values ranging from 0.009 to 21,600 milligrams of silver per kilogram of textile. Studies show that the amount of silver leached in the wash solution depends on many factors, including interactions between detergent and other chemicals and how silver is attached to the textiles.

In humans, exposure to silver can harm liver cells, skin and lungs. Prolonged exposure or exposure to a large dose can cause a condition called Argyria, in which the victim’s skin turns permanently bluish-gray.

Silver is toxic to many microbes and aquatic organisms, including zebra fish, rainbow trout and zooplankton.

Toxic effects of silver nanoparticles on zebra fish embryos. Asharani et al., 2008., CC BY

Once silver goes down the drain and ends up at wastewater treatment plants, it can potentially harm bacterial treatment processes, making them less efficient, and foul treatment equipment. More than 90 percent of silver nanoparticles released in wastewater end up in nutrient-rich biosolids left over at the end of sewage treatment, which often are used on land as agricultural fertilizers.

This poses multiple risks. If plants take up silver from soil, they could concentrate it and introduce it into the food chain. It also can leach into groundwater or wash into rivers via rainstorms or erosion.

Treating laundry water at the source

Our research shows that the most efficient way to remove silver from wastewater is by treating it in the washing machine. At this point silver concentrations are relatively high, and silver is initially released from treated clothing in a chemical form that is feasible to recover.

Once laundry washwater is piped to wastewater treatment plants and mixed with with sewage and water from other sources, silver concentrations decrease significantly and can be converted into different chemical forms.

Deer Island Wastewater Treatment Plant, Boston, Massachusetts. Doc Searls, CC BY

A bit of chemistry is helpful here. Our recovery method employs a widely used chemistry process called ion exchange. Ions are atoms or molecules that have an electrical charge. In ion exchange, a solid and a liquid are brought together and exchange ions with each other.

For example, household soaps do not lather well in “hard” water, which contains high levels of ions such as magnesium and calcium. Many home water filters use ion exchange to “soften” the water, replacing those materials with other ions that do not affect its properties in the same way.

For this process to work, the ions that switch places must both be either positively or negatively charged. Nanosilver is initially released from textiles as silver ion, which is a cation – an ion with a positive charge (hence the plus sign in its chemical symbol, Ag+).

Even at the source, removing silver from washwater is challenging. Silver concentrations in the wash solution are relatively low compared to other cations, such as calcium, that could interfere with the removal process. Detergent chemistry complicates the picture further because some detergent components can potentially interact with silver.

To recover silver without picking up other chemicals, the recovery process must use materials that have a chemical affinity for silver. In a previous study, we described a potential solution: Using ion-exchange materials embedded with sulfur-based chemicals, which bind preferentially with silver.

In our new study, we passed washwater through an ion-exchange resin column and analyzed how each major detergent ingredient interacted with silver in the water and affected the resin’s ability to remove silver from the water. By manipulating process conditions such as pH, temperature and concentration of nonsilver cations, we were able to identify conditions that maximized silver recovery.

Schematic of the silver recovery process using ion-exchange resin. Tabish Nawaz

We found that pH and the levels of calcium ions (Ca2+) were critical factors. Higher levels of hydrogen or calcium ions bind up detergent ingredients and prevent them from interacting with silver ions, so the ion-exchange resin can remove the silver from the solution. We also found that some detergent ingredients – particularly bleaching and water-softening agents – made the ion-exchange resin work less efficiently. Depending on these conditions, we recovered between 20 percent and 99 percent of the silver in the washwater.

Our findings can spur research into alternative detergent formulations that improve silver recovery. They also show that ion-exchange technology can recover trace silver from washwater that contains high levels of detergent.

The future of wastewater treatment

Today wastewater is collected from multiple sources, such as homes and businesses, and piped over long distances to centralized wastewater treatment plants. But increasing evidence shows that these facilities are ill-equipped to keep newly identified contaminants out of the environment, since they use one common treatment scheme for many different waste streams.

We believe the future is in decentralized systems that can treat different types of wastewater with specific technologies designed specifically for the materials they contain. If wastewater from laundromats contains different contaminants than wastewater from restaurants, why treat them the same way?

Our approach is both more efficient and a more effective way to address new environmental problems – potentially through a step as simple as installing a specialized water treatment cartridge in your washing machine.

This article first appeared in The Conversation

https://theconversation.com/silver-nanoparticles-in-clothing-wash-out-and-may-threaten-human-health-and-the-environment-90309

Why natural gas is the cleanest option for fossil fuel guzzling India

In the end of April, the curtain came down on the second phase of the two-week long odd-even personal vehicle plying rule in Delhi. The policy received a warm welcome from the public when it was put to the test for the first time for 15 days this January, as Delhiites more or less enjoyed congestion-free intercity rides.

Invoking the odd-even rule is widely considered as a piece of crisis action that the government was prompted to take in the wake of, among other things, a World Health Organisation (WHO) report that named Delhi, from among 1,600 cities, as the world’s most polluted city. The high concentration of particulate matter—particularly smaller than 2.5 micron diameter (PM2.5), responsible for respiratory diseases—placed the National Capital Region (NCR) in this ignoble seat. This was in 2014. The latest WHO report (May 2016) gives policy-makers a breather: PM2.5 levels have improved marginally and Delhi, in this respect, has dropped to 11th position. Don’t pop the champagne corks yet. Because PM2.5 is still 12 times over the safety limit in the NCR.

The matter in question—the quality of air in Delhiites’ lungs—is not an issue that concerns only the government of the NCR or the central government. The plain truth is that it calls for close coordination between the Centre, the NCR and multiple state governments.

Take the case of the recent proposal by the National Highways Authority of India (NHAI) to relieve NCR’s choking rush-hour traffic. The NHAI recommends building link roads, flyovers and underpasses to de-congest the NCR. Now, since the NCR comprises of districts in Haryana, Uttar Pradesh and Rajasthan—and part of its administration is in the hands of the central government—the political leadership in the NCR, participating states and the Centre would need to work hand-in-hand if this project is to take off.

NGOs, community groups, citizen journalists, environmental experts and public health specialists must keep vigil over exercises such as this to ensure the right balance between the citizens’ need for development and their right to clean air. Likewise, different administrative units must first hammer out an agreement before green regulations can be uniformly rolled out across the NCR, which includes slapping fines on violators (for example, builders who flout dust pollution norms at construction sites with impunity, users of old vehicles, etc).

The national Air Quality Index (AQI), launched by the government some time ago, is an important decision. This presents air quality values across 44 cities and 22 state capitals. The AQI score in respect of air in a city works as follows: Each pollutant is colour-coded based on its concentration in the air; the top pollutant (PM10, PM2.5, NO2, CO, O3) is identified; an overall AQI is assigned to the air in a city, which is the same as the top pollutant’s reading.

Government data has historically been cascaded to the public in spiritless and not-so-user-friendly formats. This is where AQI makes a difference. It presents real-time info on air quality in a simple five-colour-format that citizens can easily read and, based on this, plan their daily life (for example, stay indoors when pollution levels soar, pull on sneakers if the weather is looking up). The idea of giving the public cues around air quality and prompting action from them is indeed noteworthy.

More than a third of the capital city’s pollution load comes from dust. A dust management plan, which includes strict penalties for violators, is long overdue. About eight mechanised road sweepers were in operation in Delhi in June 2015; the city needs more numbers of these. Manual cleaning of roads and footpaths actually ends up “kicking up dust” and worsening pollution. In addition, it’s time India’s city administrators took steps to decentralise environment management protocols, which means even a small colony can have an air quality plan, with active participation by its residents.

Air contamination in India can also be traced back to the energy systems the country is saddled with. The answer for our policy-makers is not picking one source of energy over another. At various stages of economic growth, different energy sources have been useful and continue to be so. For instance, coal is going to be critical to the economy in the short term, and most particularly so, because extending electricity to every Indian is now the highest priority. Be that as it may, the country must start building alternatives for cutting back greenhouse emissions. In this aspect, India should, without a doubt, aggressively pursue opportunities in renewable energy.

Many of the recent policies lay stress on meeting the growing hunger for energy in rural India with solar power. However, the country cannot expect to electrify every single household using photovoltaic cells. The sheer magnitude of this sector calls for a multidimensional approach. The even-now-dominant biomass (firewood, agricultural waste and dry cattle dung), the traditional fuel in this part of the world, can’t just be wished away. Numerous technologies are now doing the rounds that enable more fuel-efficient, smoke-free and safer burning of these fuels. In the interim, large sections will move to such improvised and cleaner cook stoves. And even as they are at it, a lot of thought should go towards finding ways to bring cleaner and more mature fuels, such as biogas, within the reach of the larger masses. By doing so, energy experts can buy time, which they so badly need, to fully understand the economics and technology challenges associated with large-scale and distributed solar photovoltaic rollouts.

If India has to depend on fossil fuels, natural gas is by far the cleanest option. In the developed world, natural gas accounts for a quarter of electricity generation, whereas in India, we have only about 10% of thermal power generation capacity in the form of combined cycle gas generation turbines.

Using a mix of local and imported natural gas, the government is trying to put new life into gas-fired power stations that were idling away because of fuel shortage. This is proving a costly affair. With a view to improve the circulation of natural gas in India, policy-makers are intensifying the effort to find so far unexplored domestic natural gas deposits. This includes tapping about 63 trillion cubic feet of shale gas potential, hidden away within fine sedimentary rocks. But as a guaranteed base load capacity, natural gas will be essential in what will be potentially the world’s third largest power consumer. Therefore, natural gas can provide an assured stockpile of energy, and from this fortified position, India can tap further into its renewable energy sources.

By Tabish Nawaz

The author is a PhD fellow at University of Massachusetts, Dartmouth, in

Environmental Engineering & Sciences
Views are personal

This article first appeared in The Financial Express

https://www.financialexpress.com/opinion/why-natural-gas-is-the-cleanest-option-for-fossil-fuel-guzzling-india/281001/

एहतियात

एहतियात 

ऐ ठंडी हवा
ये  तो  बता,
                          तु आयी  कहाँ से
                          बर्फ़ गिरी है वहां,
                          तु आयी जहाँ से?

बारिश का इमकान तू लायी  है ?
मिट्टी की खुशबू तुझमें समायी है।

जिस्म   से    मेरे     तु   लिपटेगी ?
आग        इसकी         सिमटेगी ?

पेड़ों   से  पत्ते   भी   चुराएगी  तु ?
उन्हीं की ज़ुबाँ से फिर गाएगी तु ?

चिड़ियों के घोंसले वहीँ  गिर   जाएँगें।
बेघर  चहचहाते वहीँ   फिर    जाएँगें।
टूटे ख़्वाबों को, ख़्वाबों में ही बनाएँगे।

ऐ ठंडी हवा
संभल    के,
चलना ज़रा
               तुझे न मालूम, कि तेरे मचलने से
               तबाह   होतें  हैं    कुछ   मज़लूम
संभाल के रखना तु अपने कदम,
तेरे      चलने     से     है    राहत,
तेरे     मचलने       में     है  सितम।

[इमकान = Possibility]